Criticism of Cheika’s tenure increased after going down 38-13 to New Zealand in the Rugby Championship last weekend – it was the Wallabies’ fifth defeat in their last six Tests, which includes a home series loss to Ireland.
Since finishing second at the 2015 Rugby World Cup, the Australia coach has overseen just 14 victories in 33 matches.
Polota-Nau accepted the players must share the responsibility with Cheika and threw his weight behind his former Waratahs boss.
“He’s definitely the best man for the job,” said the 33-year-old hooker.
“At the end of the day he only wants what is best for the team and individuals when we have one-on-one time with him.
“He actually brings a great blueprint for us to work off. If anything, it’s more about how we take that blueprint and put it out there on the field.
“At the end of the day we’re the guys out there on the field and only we can control what the plays are at hand.
“He’s also a great motivator, getting us to be upbeat in every single session.”
— Qantas Wallabies (@qantaswallabies) August 20, 2018
He said: “We’ve got full confidence in this coaching staff and we back them 100 percent.
“There has never ever been a question about that so I don’t know where that has come from.”
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